soma
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tlc rf to lc
I have seen it recommended to adjust the eluent composition so that the material you want is at .3 rf - and then to keep adjusting it for each
component so that it continues to be at .3.
I'm getting a big separation between 2 components (like 2. and .8). I'm assuming to just keep the proportions of solvents?
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phlogiston
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Your question is not very clear.
A big separation is great, separating components is the whole purpose of TLC, isn’t it? Then what is the problem?
It would help a lot if you could explain what you are trying to do and what the problem is.
Especially this is confusing to me: “adjusting it for each component so that it continues to be at .3.”
Also the title suggests that you have a question related to LC, but you don’t mention it anywhere.
[Edited on 21-3-2017 by phlogiston]
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brubei
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i think he want to do a preparative LC of two compounds, their rf on tlc are 0.2 and 0.8 with a simple eluent.
His purpose is to adjust his eluent to get higher rf, wich means that his column will be faster. Corresponding to 0.3 for the slowest product and
>0.8 for the second.
This sounds good, however it's always good to run a column with a low quantity for a first attempt.
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soma
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Hopefully this will be clearer.
A video on chromatography at the MIT Chem site ( https://www.youtube.com/watch?v=B_QyhG2-VBI ) said to adjust the tlc rf to .3 for the component you want and then use that eluant mixture for lc.
They said that when there is more than one component wanted that you should keep adjusting the tlc mix to bring the component to .3 and then use that
for the lc.
I'm getting 2 components on tlc at ~.2 and .8. I was thinking it's good to stick with that for the lc mix.
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